1. Field of the Invention
This invention relates to a sequence of DNA which codes the main subunits of ATP synthase (ATP ase) derived from methanogenic bacteria. The methanogenic bacteria, which have been reformed by plasmids having this DNA sequence, are capable of performing the effective synthesis of ATP (adenosine triphosphate), hence they are useful as the fixing microorganism for a high efficiency methane-fermenting bio-reactor, or in the environmental treatment such as sewage disposal, etc.
2. Discussion of Background
In connection with the ATP synthase, the sequence of DNA has so far been analyzed to the fullest extent in those microorganisms such as a colon bacillus (Escherichia coli), etc., or mitochondria of eukaryotic cells. However, since the methanogenic bacterium is absolutely aerophobic and difficult to grow under ordinary conditions, its biochemical characteristics are scarcely clarified. As the consequence, there has been no example of analysis of the DNA sequence in the ATP synthase relative to the methanogenic bacteria.
Accordingly, it has not been possible to utilize the enzymes for ATP synthesis which is important to grow the methanogenic bacteria, for their improvement.
The present inventors have so far been conducting researches and studies on the ATP synthase of methanogenic bacteria (vide: a thesis by K. Inatomi, published in "Journal of Bacteriology", Vol. 167, pp 837-841 (1986)), but the sequence of the enzyme has yet to be clarified.
As the results of diligent and strenuous efforts in their studies and researches, the present inventors have succeeded in obtaining plasmids containing therein the DNA sequence which codes the ATP synthase from the methanogenic bacteria, transforming the colon bacillus "Escherichia coli" with the thus obtained plasmids, isolating the plasmids from this colon bacillus "Escherichia coli" as transformed, and finally determining the sequence of DNA which codes the essential subunits of the ATP synthase contained in the thus isolated plasmids. As the result of this success, they have arrived at the present invention.